oj.uz

답안 #446267

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
446267 2021-07-21T11:45:43 Z zxcvbnm Vudu (COCI15_vudu) C++14
140 / 140
 378 ms 39460 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define int ll
struct Ft {
    vector<ll> bit;
    int n;
    void build(vector<ll> a) {
        n = a.size()+2;
        bit.assign(n+2, 0);
    }
    void update(int idx, int x) {
        while(idx <= n) {
            bit[idx] += x;
            idx += idx & -idx;
        }
    }
    ll sum(int idx) {
        ll sum = 0;
        while(idx > 0) {
            sum += bit[idx];
            idx -= idx & -idx;
        }
        return sum;
    }
};
signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
//    freopen("test.in", "r", stdin);
    int n;
    cin >> n;
    vector<int> a(n);
    for(int& i : a) {
        cin >> i;
    }

    int p;
    cin >> p;
    vector<ll> sum = {0};
    for(int i : a) {
        sum.push_back(sum.back()+(i-p));
    }

    vector<ll> sums = sum;
    sort(sums.begin(), sums.end());

    Ft ft;
    ft.build(sums);
    ll ans = 0;
    for(ll i : sum) {
        int idx = lower_bound(sums.begin(), sums.end(), i) - sums.begin();
        ans += ft.sum(idx+1);
        ft.update(idx+1, +1);
    }
    cout << ans << "\n";
    return 0;
}

Subtask #1
140.0 / 140.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 588 KB Output is correct
2 Correct 2 ms 460 KB Output is correct
3 Correct 2 ms 460 KB Output is correct
4 Correct 378 ms 38228 KB Output is correct
5 Correct 194 ms 21844 KB Output is correct
6 Correct 318 ms 33952 KB Output is correct
7 Correct 313 ms 35188 KB Output is correct
8 Correct 278 ms 30644 KB Output is correct
9 Correct 360 ms 39460 KB Output is correct
10 Correct 312 ms 34332 KB Output is correct